Authentication system, authentication method, and computer readable medium

Abstract

An authentication system ( 1 ) includes a feature amount acquisition unit ( 11 ), a history information acquisition unit ( 12 ), an authentication unit ( 13 ), and an output unit ( 14 ). The feature amount acquisition unit ( 11 ) acquires an authentication target feature amount that is a feature amount of an authentication target image defined from an image obtained by imaging a predetermined authentication target object. The history information acquisition unit ( 12 ) acquires history information regarding an authentication history of the authentication target object on the basis of the authentication target feature amount. The authentication unit ( 13 ) performs authentication of the authentication target object on the basis of the authentication target feature amount and the history information. The output unit ( 14 ) outputs a result of the authentication.

What is claimed is: 
     
         1 . An authentication system comprising:
 at least one memory storing instructions; and   at least one processor configured to execute the instructions to:   acquire an authentication target feature amount that is a feature amount of an authentication target image defined from an image obtained by imaging a predetermined authentication target object;   acquire history information regarding an authentication history of the authentication target object on the basis of the authentication target feature amount;   perform authentication of the authentication target object on the basis of the authentication target feature amount and the history information; and   output a result of the authentication.   
     
     
         2 . The authentication system according to  claim 1 , wherein the at least one processor is further configured to execute the instructions to:
 acquire the history information including a reference feature amount of the authentication target image acquired at a time before a time at which the authentication target feature amount is acquired; and   perform the authentication by collating the authentication target feature amount with the reference feature amount.   
     
     
         3 . The authentication system according to  claim 2 , wherein the at least one processor is further configured to execute the instructions to calculate an authentication score by collating the authentication target feature amount with the reference feature amount, and perform the authentication by comparing a value of the authentication score with a predetermined threshold. 
     
     
         4 . The authentication system according to  claim 3 , wherein the at least one processor is further configured to execute the instructions to store the history information, and update the history information on the basis of the authentication. 
     
     
         5 . The authentication system according to  claim 4 , wherein the at least one processor is further configured to execute the instructions to cause the authentication target feature amount to be included in the history information as the reference feature amount after the authentication is ended. 
     
     
         6 . The authentication system according to  claim 5 , wherein the at least one processor is further configured to execute the instructions to store a plurality of the reference feature amounts respectively acquired in the authentication performed at a plurality of different times and time information at which the reference feature amount is acquired together. 
     
     
         7 . The authentication system according to  claim 6 , wherein the at least one processor is further configured to execute the instructions to perform the authentication by collating the most recent reference feature amount among the plurality of reference feature amounts with the authentication target feature amount. 
     
     
         8 . The authentication system according to  claim 6 , wherein the at least one processor is further configured to execute the instructions to also store authentication scores in the authentication corresponding to the plurality of reference feature amounts. 
     
     
         9 . The authentication system according to  claim 6 , wherein the at least one processor is further configured to execute the instructions to calculate an expected value of the authentication score related to the authentication target feature amount on the basis of a change in the authentication score with a lapse of time, and perform the authentication in consideration of the expected value in the authentication. 
     
     
         10 . The authentication system according to  claim 9 , wherein the at least one processor is further configured to execute the instructions to determine that the authentication is not able to be performed in a case where the authentication score and the expected value do not correspond to each other even in a case where it is determined that the authentication is able to be performed from comparison between the authentication score and the threshold. 
     
     
         11 . The authentication system according to  claim 4 , wherein the at least one processor is further configured to execute the instructions to:
 further store an initial feature amount related to the authentication target object in the history information; and   perform first authentication on the basis of the authentication target feature amount and the initial feature amount, and perform second authentication on the basis of the authentication target feature amount and the reference feature amount.   
     
     
         12 . The authentication system according to  claim 11 , wherein the at least one processor is further configured to execute the instructions to:
 perform the first authentication on the basis of a cumulative authentication score calculated by collating the authentication target feature amount with the initial feature amount and a reference cumulative authentication score at a most recent time point in the past; and   perform the second authentication by using the authentication score calculated by collating the authentication target feature amount with the reference feature amount and the threshold.   
     
     
         13 . The authentication system according to  claim 2 , wherein the at least one processor is further configured to execute the instructions to:
 acquire the authentication target feature amount from a plurality of the authentication target images defined in regions at least partially different from each other; and   perform the authentication on a plurality of the authentication target feature amounts, and perform the authentication by collating the plurality of authentication target feature amounts with reference feature amounts corresponding to the respective authentication target feature amounts.   
     
     
         14 . An authentication method of causing a computer to execute:
 acquiring an authentication target feature amount that is a feature amount of an authentication target image defined from an image obtained by imaging a predetermined authentication target object;   acquiring history information regarding an authentication history of the authentication target object on the basis of the authentication target feature amount;   performing authentication of the authentication target object on the basis of the authentication target feature amount and the history information; and   outputting a result of the authentication.   
     
     
         15 . A non-transitory computer readable medium storing a program for causing a computer to execute an authentication method comprising:
 acquiring an authentication target feature amount that is a feature amount of an authentication target image defined from an image obtained by imaging a predetermined authentication target object;   acquiring history information regarding an authentication history of the authentication target object on the basis of the authentication target feature amount;   performing authentication of the authentication target object on the basis of the authentication target feature amount and the history information; and   outputting a result of the authentication.